They study French at school.
French is studied at school by them.
Pictures are taken during the ceremony by the photographer.
The photographer takes pictures during the ceremony.
The passive voice if you don't know who performed the action described in the sentence
Correct
George was taken to hospital because he had a heart attack. (Why...)
Why was George taken to hospital?
We were invited by our neighbours to their party.
Passive
She visited me yesterday.
Yesterday I was visited by her.
Di Caprio was chosen as the best actor by the Academy.
The Academy chose Di Caprio as the best actor.
The passive voice is used if you want to reveal who did the action.
Incorrect.
The car was stolen between 10 pm and midnight. (When...)
When was the car stolen?
The painting was sold to an anonymous buyer.
Passive.
He is filming a movie in Cartagena.
A movie is being filmed in Cartagena.
A meeting is being held in the office.
They are holding a meeting in the office.
In the passive voice we put the object at the end of the sentence.
Incorrect
Tickets for the concert are sold at all large music stores. (Where...)
Where are the tickets for the concert sold?
Peter is going to build a house in summer.
Active
You have made the best decision.
The best decision has been made by you.
The students have been sent home by the Principal.
The principal has sent the students home.
The passive voice is used when the receiver of the action is not passive.
Incorrect
The open air concert has been cancelled. (Why...)
Why has the open air concert been cancelled?
Forty people have been injured.
Passive
We will buy a new house next summer.
A new house will be bought next summer (by us).
New Year promises will be made next new year's eve.
People will make promises next year's eve.
"The old man was murdered". Can be put in active voice?
No, because we don't know who did the action.
Portuguese is spoken in Portugal and Brazil. (Where...)
Where is Portuguese spoken?
The quiet cat secretly snuck up on the still and dirty rat and killed it using its paws.
Active